/*When Checkbox whose id is deleteAll is selected, all of other Checkboxes named deleteItem will also be selected.
Otherwise, they are not selected*/
function controlCheckbox(){
	var deleteAll = document.getElementById("deleteAll");
	var deleteItem = document.getElementsByName("deleteItem");
	for (i = 0; i < deleteItem.length; i++) {
                    if (deleteAll.checked==true) {
                        deleteItem[i].checked=true;
                    }else {
                        deleteItem[i].checked=false;
                    }
                }
}